UPPER BAINITE FORMATION MECHANISM IN FE-1.36SI-1.01CR-0.88C STEEL

In this paper it is-discussed on the mechanism of upper bainite format ion. According to the results obtained in Fe-1.36Si-1.01Cr-0.88C steel , we discovered that the primary upper bainite is formed by subunits a rranging along its long axis and steps are formed by subunits growing into different size-along the thickness, the macro-plane of the primar y upper bainite plate is the same as the basal plane (shear plane), th e formation mechanism of the primary upper bainite plate is the nuclea tion-growth mechanism of subunits shearing one by one along long axis, controlled by diffusion.